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1. Crop Production and Management

This chapter talks about cultivation of plants on a large scale and the various farming activities involved.

All living organisms need food to survive and to carry out various body functions like Digestion, Respiration and Excretion. Their need for food is fulfilled by systematic cultivation of food giving plants

 1.1      Crop

Cultivation of plants of same kind on a large scale is called Crop. Crops can be classified into two types based on the season in which they are sown

 

 

Kharif

Rabi

Season of sowing Rainy season Winter season
Cultivation period June to September October to March
Example of such crops Paddy, maize and SoybeansPulses and vegetables are grown during summer Wheat, Gram, Pea and Mustard

 

1.2      Basic Practices of Crop Production

The following are the main activities involved in crop production

  1. Preparation of Soil
  2. Sowing
  3. Adding manure and fertilizers
  4. Irrigation
  5. Protection from weeds
  6. Harvesting
  7. Storage

1.2.1      Preparation of Soil

It is the first and an important step before growing a crop. This involves turning the soil & loosening it so that roots can penetrate deep into the soil and also allows the roots to breathe easily. Loosening of soil helps in the growth of earthworms & microbes which further loosen the soil & also add humus to it.

Need for the soil to be loosened – Soil is rich in minerals, water, air & some living organisms. The dead plants and animals when decomposed, release nutrients back in the soil making it nutrient-rich. Loosening of soil brings the nutrient, rich soil to the top for the plants to use for their growth.

The process of loosening and turning the soil is called Tilling or Ploughing. Tilling / Ploughing is done by using Ploughs made of wood & iron. Big pieces of soil or crumbs left in the ploughed field are broken with the help of a plank. Levelling of soil is done with the help of a leveller which is important for the purpose of Sowing & Irrigation. Tilling also ensures proper mixing of manure with soil. A hoe is also sometimes used for removing weeds and for ploughing

These days, ploughing is done using a Cultivator connected to a tractor. This saves labour and time as compared to an animal driven ploughs.

DIAGRAM

 1.2.2      Sowing

Sowing is the most important part of crop production as it decides the final yield. Good quality seeds that are clear and healthy are selected by the farmers to get a high yield. Good seeds can be separated from damaged ones by putting them into water. Damaged seeds are hollow and float on the water while good quality, healthy seeds settle at the bottom.

There are two types of sowing tools

  1. Traditional Tool is a funnel shaped tool which is filled with seeds, while sowing, seeds are passed down through pipes having sharp ends. The ends are sharp as they pierce into the soil and put the seeds there
  2. Seed Drill is the modern day tool for sowing seeds & is used with the help of tractors. This tool has an edge over the traditional tool as it sows the seeds uniformly at proper distances & depths. It also covers the seeds with soil after sowing which prevents damage caused by birds. Seed Drill saves time & labour

Wonder why an appropriate distance between the seeds is important?

This is to avoid overcrowding which ensures that each plant gets sufficient sunlight, nutrients & water from the soil.

DIAGRAM

 

1.2.3   Adding Manure & Fertilizers

Continuous growing of crops makes the soil poorer in nutrients. To yield a good crop regularly, we need to artificially replenish the soil with nutrients. The substances which are added to the soil in the form of nutrients for the healthy growth of plants are called Manure & Fertilizers and the process is called Manuring.

Difference between Manure & Fertilizer


Manure

Fertilizer

It is an organic substance obtained from decomposition of plant & animal waste It is an inorganic substance rich in specific nutrients
It is obtained from plant & animal waste dumped in open pits & letting it to decompose by microorganisms It is produced in factoriesExamples of fertilizers – Urea, Ammonium Sulphate, Super Phosphate, Potash and NPK (Nitrogen, Phosphorous & Potassium)
It improves the soil texture, makes it porous and promotes water retention It does not improve the water retention properties of soil
It is less rich in nutrients but replenishes the soil with balanced set of nutrients It is very rich in specific nutrients. Specific nutrients, which are relevant for a particular crop can also be added selectively. This improves the yield of crops like wheat and rice(paddy)However, excessive use makes the soil less fertile
It is non-polluting & maintains the eco-system It is a source of water pollution as the ground water table can get contaminated with salts present in the Fertilizers


There is another natural way of replenishing the nutrients back into the soil called Crop Rotation. It is the practice of growing different crops alternately. It is a good method of replenishing the soil with nutrients and farmers are encouraged to adopt this practice.

Example – In northern India, wheat is grown in one season and legumes are grown as fodder in the other season.

Why just by growing legumes, soil becomes nutrient-rich?

This is so, because Rhizobium bacteria are present in the nodules of the roots of leguminous plants which fix atmospheric nitrogen.

 1.2.4      Irrigation

The supply of water to crops at different intervals is called Irrigation. Irrigation is important because

  1. Water is essential for the germination of seeds. Water is absorbed by the roots of plants & along with water, minerals and fertilizers are also absorbed. Nutrients get dissolved in water and then get transported to all parts of the plants.
  2. Water protects the crop from frost and hot air currents.

Time & Frequency of irrigation differs for different crops depending on

  1. Type of Crop
  2. Type of Soil
  3. Season

The different Sources of Irrigation are

  1. Wells
  2. Tubewells
  3. Ponds
  4. Lakes
  5. Rivers
  6. Dams
  7. Canals

The different Methods of Irrigation are

  1. Traditional Methods
  2. Modern Methods

Traditional Methods use cattle & human labour to lift and pump water into the fields. They are cheaper but less efficient. Water is drawn from lakes & canals. Various traditional ways are

  1. Moat (Pulley – System)
  2. Chain Pump
  3. Dhekli
  4. Rahat

These days, pumps are commonly used for lifting water using.

Modern Methods of Irrigation use Diesel, Biogas, Electricity and Solar energy for lifting water.  They are more efficient and also use water economically. Different methods are

  1. Sprinkler System: This system has a network of perpendicular pipes which have rotating nozzles on top. These pipes are joined to the main pipeline at regular intervals. When water flows through the main pipe under pressure, it escapes from the rotating nozzles. Water gets sprinkled on the crop as if it is raining. It is more useful on the uneven and sandy land where sufficient water is not available.
  2. Drip System: This system provides water to plants drop by drop just at the position of the roots. Best technique for watering fruit plants, gardens & trees. They are very efficient as water is not wasted at all.

DIAGRAM

 1.2.5      Protection from Weeds

The undesirable and uncultivated plants that grow naturally along with the crop are called Weeds

The process of removal of weeds is called weeding. Weeding is necessary because weeds compete with the crop plants for water, nutrients, space & light, thus affecting the growth of the crop.

Various ways of Weeding are

  1. Tilling before sowing of crops helps in uprooting & killing of weeds.
  2. Manual removal by uprooting weeds or by cutting them close to the ground.

Weeds are also controlled by spraying certain chemicals called Weedicides.

 1.2.6      Harvesting

The cutting of crop after it is mature is called Harvesting. Harvesting is either done manually by sickle or by a machine called Harvester.

Once the crops are harvested, we need to extract grains from the harvest. The process of separating the grain from the chaff is called as Threshing. Threshing is carried out with the help of a machine called ‘combine’ which is a combination of harvester & thresher.

Another process of separation of grain & chaff using simpler machines is called winnowing. This is used by farmers with small holdings of land.

DIAGRAM

 1.2.7      Storage

Storage of the final produce is very important. Before storing the grains, they are properly dried in the sun as it ensures that they are moisture free & are safe from insects, rats & microorganisms. This also prevents the attack by insect pests, bacteria & fungi.

Large scale storage of grains is done in silos & granaries to protect them from pests like rats & insects. For storing large quantities of grains for longer time, specific chemical treatments are done to protect them from pests & microorganisms.

DIAGRAM

1.3      Animal Husbandry

Food is obtained from animals for which animals are reared & are provided with proper food & shelter. This is called as Animal Husbandry. Examples of food obtained from animals are

  1. Eggs
  2. Milk
  3. Meat